Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0
/*
 * I/O Processor (IOP) ADB Driver
 * Written and (C) 1999 by Joshua M. Thompson (funaho@jurai.org)
 * Based on via-cuda.c by Paul Mackerras.
 *
 * 1999-07-01 (jmt) - First implementation for new driver architecture.
 *
 * 1999-07-31 (jmt) - First working version.
 */
 
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/init.h>
 
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_iop.h>
#include <asm/adb_iop.h>
#include <asm/unaligned.h>
 
#include <linux/adb.h>
 
static struct adb_request *current_req;
static struct adb_request *last_req;
static unsigned int autopoll_devs;
static u8 autopoll_addr;
 
static enum adb_iop_state {
<------>idle,
<------>sending,
<------>awaiting_reply
} adb_iop_state;
 
static void adb_iop_start(void);
static int adb_iop_probe(void);
static int adb_iop_init(void);
static int adb_iop_send_request(struct adb_request *, int);
static int adb_iop_write(struct adb_request *);
static int adb_iop_autopoll(int);
static void adb_iop_poll(void);
static int adb_iop_reset_bus(void);
 
/* ADB command byte structure */
#define ADDR_MASK       0xF0
#define OP_MASK         0x0C
#define TALK            0x0C
 
struct adb_driver adb_iop_driver = {
<------>.name         = "ISM IOP",
<------>.probe        = adb_iop_probe,
<------>.init         = adb_iop_init,
<------>.send_request = adb_iop_send_request,
<------>.autopoll     = adb_iop_autopoll,
<------>.poll         = adb_iop_poll,
<------>.reset_bus    = adb_iop_reset_bus
};
 
static void adb_iop_done(void)
{
<------>struct adb_request *req = current_req;
 
<------>adb_iop_state = idle;
 
<------>req->complete = 1;
<------>current_req = req->next;
<------>if (req->done)
<------><------>(*req->done)(req);
 
<------>if (adb_iop_state == idle)
<------><------>adb_iop_start();
}
 
/*
 * Completion routine for ADB commands sent to the IOP.
 *
 * This will be called when a packet has been successfully sent.
 */
 
static void adb_iop_complete(struct iop_msg *msg)
{
<------>unsigned long flags;
 
<------>local_irq_save(flags);
 
<------>adb_iop_state = awaiting_reply;
 
<------>local_irq_restore(flags);
}
 
/*
 * Listen for ADB messages from the IOP.
 *
 * This will be called when unsolicited IOP messages are received.
 * These IOP messages can carry ADB autopoll responses and also occur
 * after explicit ADB commands.
 */
 
static void adb_iop_listen(struct iop_msg *msg)
{
<------>struct adb_iopmsg *amsg = (struct adb_iopmsg *)msg->message;
<------>u8 addr = (amsg->cmd & ADDR_MASK) >> 4;
<------>u8 op = amsg->cmd & OP_MASK;
<------>unsigned long flags;
<------>bool req_done = false;
 
<------>local_irq_save(flags);
 
<------>/* Responses to Talk commands may be unsolicited as they are
<------> * produced when the IOP polls devices. They are mostly timeouts.
<------> */
<------>if (op == TALK && ((1 << addr) & autopoll_devs))
<------><------>autopoll_addr = addr;
 
<------>switch (amsg->flags & (ADB_IOP_EXPLICIT |
<------><------><------>       ADB_IOP_AUTOPOLL |
<------><------><------>       ADB_IOP_TIMEOUT)) {
<------>case ADB_IOP_EXPLICIT:
<------>case ADB_IOP_EXPLICIT | ADB_IOP_TIMEOUT:
<------><------>if (adb_iop_state == awaiting_reply) {
<------><------><------>struct adb_request *req = current_req;
 
<------><------><------>if (req->reply_expected) {
<------><------><------><------>req->reply_len = amsg->count + 1;
<------><------><------><------>memcpy(req->reply, &amsg->cmd, req->reply_len);
<------><------><------>}
 
<------><------><------>req_done = true;
<------><------>}
<------><------>break;
<------>case ADB_IOP_AUTOPOLL:
<------><------>if (((1 << addr) & autopoll_devs) &&
<------><------>    amsg->cmd == ADB_READREG(addr, 0))
<------><------><------>adb_input(&amsg->cmd, amsg->count + 1, 1);
<------><------>break;
<------>}
<------>msg->reply[0] = autopoll_addr ? ADB_IOP_AUTOPOLL : 0;
<------>msg->reply[1] = 0;
<------>msg->reply[2] = autopoll_addr ? ADB_READREG(autopoll_addr, 0) : 0;
<------>iop_complete_message(msg);
 
<------>if (req_done)
<------><------>adb_iop_done();
 
<------>local_irq_restore(flags);
}
 
/*
 * Start sending an ADB packet, IOP style
 *
 * There isn't much to do other than hand the packet over to the IOP
 * after encapsulating it in an adb_iopmsg.
 */
 
static void adb_iop_start(void)
{
<------>struct adb_request *req;
<------>struct adb_iopmsg amsg;
 
<------>/* get the packet to send */
<------>req = current_req;
<------>if (!req)
<------><------>return;
 
<------>/* The IOP takes MacII-style packets, so strip the initial
<------> * ADB_PACKET byte.
<------> */
<------>amsg.flags = ADB_IOP_EXPLICIT;
<------>amsg.count = req->nbytes - 2;
 
<------>/* amsg.data immediately follows amsg.cmd, effectively making
<------> * &amsg.cmd a pointer to the beginning of a full ADB packet.
<------> */
<------>memcpy(&amsg.cmd, req->data + 1, req->nbytes - 1);
 
<------>req->sent = 1;
<------>adb_iop_state = sending;
 
<------>/* Now send it. The IOP manager will call adb_iop_complete
<------> * when the message has been sent.
<------> */
<------>iop_send_message(ADB_IOP, ADB_CHAN, req, sizeof(amsg), (__u8 *)&amsg,
<------><------><------> adb_iop_complete);
}
 
static int adb_iop_probe(void)
{
<------>if (!iop_ism_present)
<------><------>return -ENODEV;
<------>return 0;
}
 
static int adb_iop_init(void)
{
<------>pr_info("adb: IOP ISM driver v0.4 for Unified ADB\n");
<------>iop_listen(ADB_IOP, ADB_CHAN, adb_iop_listen, "ADB");
<------>return 0;
}
 
static int adb_iop_send_request(struct adb_request *req, int sync)
{
<------>int err;
 
<------>err = adb_iop_write(req);
<------>if (err)
<------><------>return err;
 
<------>if (sync) {
<------><------>while (!req->complete)
<------><------><------>adb_iop_poll();
<------>}
<------>return 0;
}
 
static int adb_iop_write(struct adb_request *req)
{
<------>unsigned long flags;
 
<------>if ((req->nbytes < 2) || (req->data[0] != ADB_PACKET)) {
<------><------>req->complete = 1;
<------><------>return -EINVAL;
<------>}
 
<------>req->next = NULL;
<------>req->sent = 0;
<------>req->complete = 0;
<------>req->reply_len = 0;
 
<------>local_irq_save(flags);
 
<------>if (current_req) {
<------><------>last_req->next = req;
<------><------>last_req = req;
<------>} else {
<------><------>current_req = req;
<------><------>last_req = req;
<------>}
 
<------>if (adb_iop_state == idle)
<------><------>adb_iop_start();
 
<------>local_irq_restore(flags);
 
<------>return 0;
}
 
static void adb_iop_set_ap_complete(struct iop_msg *msg)
{
<------>struct adb_iopmsg *amsg = (struct adb_iopmsg *)msg->message;
 
<------>autopoll_devs = get_unaligned_be16(amsg->data);
<------>if (autopoll_devs & (1 << autopoll_addr))
<------><------>return;
<------>autopoll_addr = autopoll_devs ? (ffs(autopoll_devs) - 1) : 0;
}
 
static int adb_iop_autopoll(int devs)
{
<------>struct adb_iopmsg amsg;
<------>unsigned long flags;
<------>unsigned int mask = (unsigned int)devs & 0xFFFE;
 
<------>local_irq_save(flags);
 
<------>amsg.flags = ADB_IOP_SET_AUTOPOLL | (mask ? ADB_IOP_AUTOPOLL : 0);
<------>amsg.count = 2;
<------>amsg.cmd = 0;
<------>put_unaligned_be16(mask, amsg.data);
 
<------>iop_send_message(ADB_IOP, ADB_CHAN, NULL, sizeof(amsg), (__u8 *)&amsg,
<------><------><------> adb_iop_set_ap_complete);
 
<------>local_irq_restore(flags);
 
<------>return 0;
}
 
static void adb_iop_poll(void)
{
<------>iop_ism_irq_poll(ADB_IOP);
}
 
static int adb_iop_reset_bus(void)
{
<------>struct adb_request req;
 
<------>/* Command = 0, Address = ignored */
<------>adb_request(&req, NULL, ADBREQ_NOSEND, 1, ADB_BUSRESET);
<------>adb_iop_send_request(&req, 1);
 
<------>/* Don't want any more requests during the Global Reset low time. */
<------>mdelay(3);
 
<------>return 0;
}